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Solve problems involving percentages, rates, and proportions · Grade 9 · B3.5

Name: ______________________

Date: ______________________

1
What is 45% of 180?
Warm-up
Answer:
2
What is 20% of 20?
Warm-up
Answer:
3
What is 20% of 60?
Warm-up
Answer:
4
4 notebooks cost $12. At the same rate, how much do 8 notebooks cost?
On level
Answer:
5
2 notebooks cost $18. At the same rate, how much do 7 notebooks cost?
On level
Answer:
6
2 notebooks cost $10. At the same rate, how much do 5 notebooks cost?
On level
Answer:
7
A jacket costs $20. Its price rises by 30%. What is the new price?
Challenge
Answer:
8
A jacket costs $140. Its price rises by 70%. What is the new price?
Challenge
Answer:
9
A jacket costs $120. Its price rises by 30%. What is the new price?
Challenge
Answer:

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Worksheet code: eyJzIjoibnVtYmVyLXBlcmNlbnQtcHJvcG9ydGlvbiIsImQiOlsxMDU3ODA4NTQwLDE2MDQ0NjU1MjksMjgwODMwNjg4LDE5NzMwODk5MDgsMTc3NTk2ODAyNSw5OTYxOTAyODUsMTI4NzM4ODIxOSwyMDM1Njk1MTMyLDEzNDQ5NzA0NDJdLCJ2IjoxfQ.c64ceaf912ba

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Answer key · Solve problems involving percentages, rates, and proportions

1.
81 — 45% of 180 = 45/100 × 180 = 81.
2.
4 — 20% of 20 = 20/100 × 20 = 4.
3.
12 — 20% of 60 = 20/100 × 60 = 12.
4.
24 — Each notebook costs $12 ÷ 4 = $3, so 8 cost 8 × $3 = $24.
5.
63 — Each notebook costs $18 ÷ 2 = $9, so 7 cost 7 × $9 = $63.
6.
25 — Each notebook costs $10 ÷ 2 = $5, so 5 cost 5 × $5 = $25.
7.
26 — The increase is 30% of $20 = $6, so the new price is $20 + $6 = $26.
8.
238 — The increase is 70% of $140 = $98, so the new price is $140 + $98 = $238.
9.
156 — The increase is 30% of $120 = $36, so the new price is $120 + $36 = $156.